Pretty good. Except for the last statement.

Meaning, that one may be good, too - but I haven't seen (heard) an instance of such in my life, after I moved on from an AV receiver with captive cord.

Granted, I've never owned any single piece of electronics that exceeds price of $10,000 new (and, of course, actually paid way less than that used). However, I've owned enough below that price cutoff, to state with confidence that the only reason power cord would NOT affect sound quality is the insufficient overall resolution of the system and/or - but that's my speculation - indiscriminate hearing.

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